Introduction. Obesity and obstructive sleep apnea syndrome OSA are common coexisting conditions associated with a chronic low-grade inflammatory state underlying some of the cognitive, metabolic, and cardiovascular morbidities. Aim. To examine the levels of inflammatory markers in obese community-dwelling children with OSA, as compared to no-OSA, and their association with clinical and polysomnographic PSG variables. Methods. In this cross-sectional, prospective multicenter study, healthy obese Spanish children ages 4–15 years were randomly selected and underwent nocturnal PSG followed by a morning fasting blood draw. Plasma samples were assayed for multiple inflammatory markers. Results. 204 children were enrolled in the study; 75 had OSA, defined by an obstructive respiratory disturbance index RDI of 3 events-hour total sleep time TST. BMI, gender, and age were similar in OSA and no-OSA children. Monocyte chemoattractant protein-1 MCP-1 and plasminogen activator inhibitor-1 PAI-1 levels were significantly higher in OSA children, with interleukin-6 concentrations being higher in moderate-severe OSA i.e., AHI > 5-hrTST; , while MCP-1 levels were associated with more prolonged nocturnal hypercapnia . Conclusion. IL-6, MCP-1, and PAI-1 are altered in the context of OSA among community-based obese children further reinforcing the proinflammatory effects of sleep disorders such as OSA. This trial is registered with ClinicalTrials.gov NCT01322763.